The Canberra preschooler was diagnosed with an aggressive tumour at the base of her brain, making surgery and treatment all but impossible.

After a round of radiation therapy, the family were told to take Annabelle home and "make memories". There was nothing more the doctors could do.

Instead, the Potts family have searched the world for a cure. Annabelle's tumour was deemed too risky for clinical trials back home and in the UK, so in June the family pooled their resources to fly the four year old to Mexico.

There they joined a community of desperate families from around the world seeking experimental treatment for the rare cancer known as Diffuse Intrinsic Pontine Glioma (DIPG).

Brain cancer kills more children in Australia than any other disease, and rare or less common cancers account for more than 40 per cent of all cancer deaths. Yet they receive only 13.5 per cent of research funding.

Patients are twice as likely to die as those with common cancers, and, like Annabelle, often have difficulty accessing clinical trials into new treatments.

Last week, a Senate committee report called on the federal government to make research into cancers with low survival rates a national health priority.

It also recommended state governments fund travel and accommodation expenses for patients in clinical trials.

Annabelle's early results from the Mexico treatment were "remarkable", mother Kathie Griffiths said.

Within a few months of the unique form of intra-arterial chemotherapy, doctors back home confirmed Annabelle's tumour had shrunk and her symptoms had all but disappeared, though they were unable to say if it was the Mexico treatment that was responsible.

"Before she was vomiting every single day, she couldn't go to daycare, she'd be having meltdowns, but two days after her first treatment [in Mexico], that all stopped," Ms Griffiths said.

When Annabelle returned to daycare in Canberra this September, she was a "normal four-year-old girl" again.

But the therapy has taken its toll on the Potts family's finances. Each treatment in Mexico costs about $25,000, not including the cost of flights and accommodation. And, having exhausted all personal leave, father Adam now loses a week of income every six weeks when he flies to Mexico with Annabelle for another round of the therapy.

Receiving just $130 a fortnight in carer's support, the family now rely on community fundraising and live from one treatment to the next.

"The Canberra community is literally funding us to save our daughter," Ms Griffiths said.

Dr Robert De Rose co-founded the Isabella and Marcus Paediatric Brainstem Tumour Fund, which helps fund research into rare brain cancers, after his six-year-old daughter Isabella died of DIPG in 2008. He said, in more than 30 years, the survival rate for Australians with brain cancer had not improved.

"We need more clinical trials here in Australia so parents don't have to do desperate things like go overseas or mortgage their homes and raise tens of thousands of dollars," he said.

"It will get better, but the Potts family are caught in the middle right now."

Dr De Rose also called for equity in research funding, so scientists looking into rarer forms of cancer had access to the money they needed.

"If you can fund the research, you can find the cure," Dr De Rose said.

In September, a "break-through" clinical trial, which sees doctors and scientists work together to personalise treatments for children with the most aggressive forms of cancer, was launched by the Children's Cancer Institute and the Kids Cancer Centre at Sydney Children's Hospital.

Up to 400 children are expected to be enrolled over the next three years, but for Annabelle, who has a less than a 1 per cent chance of survival, Ms Griffiths said the trial is not an option.

Patients in the study must have a biopsy to take a sample of their tumour, and doctors say the procedure is too risky in her case. It's the latest heart-breaking setback after months and months of research, Ms Griffiths said.

"She's just not eligible for anything at all.

"We heard about another trial where we were told perhaps they could give her the drugs on compassionate grounds but [it was] another no."

While Annabelle is back in Mexico this week receiving treatment, Ms Griffiths said the family did not have enough money to cover the next round.

Finances were also part of the reason they had spaced out Annabelle's treatments in consultation with her doctors.

Recently the little girl sailed past the nine month life expectancy doctors gave her in December.

With emotion, Ms Griffiths said the family had now enrolled Annabelle in a Canberra preschool.

"I didn't think it would ever happen but I'm making plans for her future," she said.

"We're not doing what the doctors have said, we're not just making memories. We're making life happen."

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